Apparatus and method for tissue and organ stabilization

ABSTRACT

A system for locally stabilizing an anastomotic site of a vessel of a beating heart during a surgical procedure is disclosed. The system includes bonding a pad to the myocardium and attaching a control arm to the pad, all by use of a bioabsorbable adhesive. The control arm is grasped and manipulated by a retractor thereby stabilizing the anastomotic area during the surgical procedure. The pad is optional and can be ommitted in one embodiment where the control arm has feet that are directly bonded to tissue. The pad may also have barbs or can include suction cups. The pad can include a helix-shaped fastener or a mechanical fastener that can be easily linked or hooked to a surgical instrument for manipulation.

RELATED APPLICATION

This application is a divisional application entitled to priority fromapplication Ser. No. 08/774,855, filed on Dec. 18, 1996, now issued asU.S. Pat. No. 5,921,979.

The present invention relates to an apparatus and method for stabilizingan area of tissue during a surgical procedure. More precisely, thepresent invention is directed to an apparatus and method to manipulateand locally stabilize an anastomotic site during a beating heartcoronary artery bypass grafting procedure.

BACKGROUND OF THE INVENTION

Various cardiovascular procedures have been performed for many yearstypically by opening the sternum (referred to as a median sternotomy),and connecting the patient to cardiopulmonary bypass equipment tomaintain the circulation of oxygenated blood throughout the patient'scirculatory system. In this manner, the heart can be stopped and varioussurgical procedures performed such as coronary artery bypass graftingand replacement of aortic, mitro, and other heart valves. Numerous othersurgical procedures have been performed in a similar manner.

During minimally invasive coronary artery bypass procedures using thebeating heart approach, the region of the heart which receives the graftvessel must be stabilized. Presently, this is often performed bythreading two suture or silicone rubber strands through the myocardiumwith curved needles, on either side of the recipient coronary artery atthe site of the distal anastomosis. The silicone strands are tensionedto lift the heart and to hold the coronary artery stationary. Suture orsilicone strands with curved needles swaged on one end are available forthis use.

Placement of the suture or silicone loops may be somewhat difficult, asthe heart is beating. The tip of the needle must be placed on the heart,and rotation of the surgeon's wrists must be performed to insert theneedle through the myocardium. Unpredictable motion of the epicardialsurface during needle placement may cause laceration of the heart orpuncture of a coronary artery. It is therefore useful to stabilize theanastomotic area during the surgical procedure.

There are devices and methods that facilitate the performance of cardiacprocedures such as heart valve repair and replacement, coronary arterybypass grafting, and the like, using minimally invasive techniques toeliminate the need for a gross thoracotomy. For example, U.S. Pat. No.5,425,705 to Evard et al. discloses an apparatus and method forthoracoscopically arresting the heart and establishing cardiopulmonarybypass, thus facilitating a variety of less-invasive surgical procedureson and within the heart and great vessels of the thorax. In oneembodiment, Evard provides a thoracoscopic system for arresting apatient's heart including a clamp configured for introduction into thepatient's thoracic cavity through a percutaneous intercostal penetrationin the patient's chest. The clamp is positionable about the patient'sascending aorta between the coronary arteries and the brachiocephalicartery. The clamp is coupled to the distal end of an elongated handlefor manipulating the clamp from a location outside of the patient'sthoracic cavity. It is known to use surgical clips or clamps for thepurpose of clamping vessels or manipulating tissue. Typically, suchclamps have a pair of movable jaws biased by a spring into a closedposition, allowing the clamp to be placed on a vessel or portion oftissue and be firmly retained thereon. Examples of such clamps can befound in U.S. Pat. No. 4,932,955 to Merz et al.; U.S. Pat. No. 4,605,990to Wilder et al.; 5,074,870 to Von Zeppelin; U.S. Pat. No. 3,809,094 toCook; U.S. Pat. No. 4,404,677 to Springer; U.S. Pat. No. 4,051,844 toChiulli; and U.S. Pat. No. 4,988,355 to Leveen et al.

Outside of the field of cardiac surgery, U.S. Pat. No. 5,415,666 toGourlay et al. discloses a tethered clamp retractor used for tissuemanipulation. The tissue manipulation system includes a tethered clamp,a clamp applicator for positioning the clamp through a trocar sleeve andapplying the clamp to a tissue location in the abdominal cavity, and arigid positioning shaft for engaging the clamp and/or tether tomanipulate the clamp.

In view of the shortcomings of the prior art devices, there is aspecific need for an apparatus and method for locally stabilizing ananastomotic site during a beating heart coronary artery graftingprocedure.

SUMMARY OF THE INVENTION

The present invention is directed to a system and method for locallystabilizing an anastomotic site of a beating heart during a cardiacsurgical procedure. In a preferred embodiment, the present inventionsystem includes a pad of bioabsorbable adhesive attached to an area ofcardiac tissue, means for controlling the pad and thereby manipulatingthe area of cardiac tissue to create a locally stable area, and meansfor bonding the pad to the area of tissue. A retractor is used to graspthe means for controlling the pad, which means may be a rigid controlarm. In a preferred method of the present invention, the procedurecomprises exposing and drying off the anastomotic area of the heart'ssurface, placing a structural component or pad in the form of abioabsorbable glue to tissue adjacent the coronary artery, letting theglue cure, attaching a retractor to the structural component or pad, andmanipulating the structural component to minimize movement and stabilizethe anastomotic site surrounding the artery.

In an alternative embodiment, the present invention provides a systemfor locally stabilizing the myocardium adjacent to an anastomotic siteof a coronary artery of a beating heart during a surgical procedure, thesystem having a first helix-shaped fastener inserted into the myocardiumadjacent the coronary artery, a second helix-shaped fastener insertedinto the myocardium adjacent the coronary artery, and at least onesuture attached to each of the first and second helix fasteners wherebythe sutures are tensioned to stabilize the myocardium and the coronaryartery.

In the exemplary embodiment, the present invention employs a strand ofsuture attached to the helix-shaped fastener. The helix-shaped fasteneris inserted into the myocardium adjacent the anastomotic site of thecoronary artery by means of a mechanical insertion device. A secondhelix-shaped fastener is inserted on the opposite side of the artery andtension is applied to suspend and stabilize the anastomotic site.Because the helix-shaped fastener involves placement of the tip of thedevice on the heart and depression of the insertion device handle, it isfaster and simpler than use of the conventional curved needle insertion.The helix-shaped fastener advances axially, similar to that of acorkscrew, into the myocardium, and the rotational maneuver of aconventional needle placement is avoided. In the preferred embodiment,the helix-shaped fastener is manufactured form a rigid, bioabsorbablematerial. Rigidity of the fastener is required to allow insertion intothe myocardium; use of a bioabsorbable material allows the fastener tobe left in the heart tissue following coronary bypass without need forits removal. The suture attached to the fastener may also bebioabsorbable, such that following use, the suture may be cut close tothe fastener and the remaining short end left behind as well.

The sutures may be attached to a frame outside the surface of the skinof the patient; the frame may encircle the limited thoracotomy, orsternotomy used for cardiac access. Alternatively, the sutures may beattached to a frame which in turn is attached to the operating table. Itis anticipated that two helix-shaped fasteners be used on opposite sidesof a coronary artery for stabilization, although additional helix-shapedfasteners may be added as needed.

These and other advantages of the present invention will become apparentfrom the following detailed description thereof when taken inconjunction with the accompanying exemplary drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a preferred embodiment of the presentinvention in use to locally stabilize an anastomotic site during acoronary artery bypass grafting procedure.

FIG. 2 is a perspective view of a preferred embodiment of the presentinvention attached to the myocardium.

FIG. 3 is a side elevational view of an alternative embodiment of thepresent invention using mechanically linked fasteners.

FIG. 4 is a side elevational view of an alternative embodiment of thepresent invention having a pad with barbs that are embedded in themyocardium.

FIG. 5 is a side elevational view of an alternative embodiment of thepresent invention wherein helix-shaped fasteners are used to locallystabilize the anastomotic site.

FIGS. 6(a) and (b) are a side elevational view and a top plan view,respectively, of a preferred embodiment of the present inventionhelix-shaped fastener.

FIG. 7 is a side elevational view of an alternative embodiment of thepresent invention having control arms with feet directly bonded to themyocardium.

FIG. 8 is a side elevational view of an alternative embodiment of thepresent invention providing a pad with suction cups that adhere-to theepicardium.

FIG. 9 is a side elevational view of an alternative embodiment of thepresent invention.

FIG. 10 is a partial perspective view of the embodiment of FIG. 9.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is directed to a system and method for locallystabilizing an anastomotic site of a beating heart during a cardiacsurgical procedure. While the present invention is described in detailas applied to minimally invasive coronary artery bypass graft procedureson a beating heart, those skilled in the art will appreciate that thepresent invention can be applied to other surgical procedures andinternal organs as well where locally stabilizing tissue is a primaryconcern.

FIG. 1 is a perspective view of a conventional cardiopulmonary bypassprocedure. As taught by conventional techniques, cardiopulmonary bypassis established by a venous cannula that is introduced into a major veinsuch as the inferior vena cava, or into the heart 5 itself, to withdrawdeoxygenated blood from the patient and route it to a cardiopulmonarybypass (CPB) machine for oxygenation. Generally, an arterial cannula isintroduced into a major artery such as the aorta, or a femoral artery,to deliver oxygenated blood from the cardiopulmonary bypass machine tothe patient's arterial system.

In surgical procedures where cardiac function is arrested, the heart andcoronary arteries must be isolated from the patient's arterial system.Using conventional techniques, the sternum is cut longitudinally,referred to as a median sternotomy, to provide access to the heart andother thoracic vessels. One method taught in the prior art is tomechanically cross-clamp the ascending aorta 1 with a clamp 2 downstreamof the ostia of the coronary arteries, but upstream of thebrachiocephalic artery, which allows oxygenated blood from thecardiopulmonary bypass machine to reach the arms, neck, head, and theremainder of the body. A catheter 3 can then be introduced into theascending aorta 1 between the cross-clamp 2 and the aortic valve.Cardioplegic fluid is then infused through the catheter 3 and into thecoronary arteries. The venous cannula 4 introduced into the heart 5withdraws deoxygenated blood from the patient and routes it to thecardiopulmonary bypass machine for oxygenation.

The pericardium in FIG. 1 has been omitted for clarity. FIG. 1 furthershows a preferred embodiment of the present invention attached tomyocardium 6. In this embodiment, pads 7 are attached to the myocardium6 adjacent to and on either side of coronary artery 10. The pads 7 canbe formed from a bioabsorbable adhesive that attaches directly to themyocardium, as will be further described herein. While pads 7 in FIG. 1are depicted as a rectangular-shaped patch on the myocardium, inpractice it is more likely to resemble a highly viscous and flowableadhesive that will flow onto the myocardium and provide a surface thatcan be manipulated. In keeping with the invention, a surgicalinstrument, such as a known grasper or retractor (not shown) is used tograsp and manipulate pads 7 and hence the myocardium, to lift andstabilize the tissue of the anastomotic area 16 surrounding coronaryartery 10. To facilitate manipulation of pads 7, control arms 8 areattached to the pads. The control arms can either be flexiblebioabsorbable material, such as suture thread adhesively attached to thepads, or a more rigid material attached to the pads. The retractor orgrasper is used to removably grip control arms 8 and pull and lift thetissue to stabilize the area 16 around coronary artery 10 as described.

In another preferred embodiment, as shown in FIGS. 1 and 2, the presentinvention provides pads 7 adhesively bonded to myocardium 6. Further,control arm 8 is attached to each of the respective pads 7. Thesecontrol arms 8 have an attachment member 9 that permit a surgicalinstrument, such as a retractor (not shown), to manipulate control arm 8when gripping attachment member 9. Accordingly, when the retractorcontrols the movement of control arm 8, pad 7 and the cardiac tissuedirectly beneath are stabilized so that anastomotic site 16 is likewisestabilized for the subsequent grafting procedure.

Although FIG. 1 shows a surgical procedure wherein the cardiac functionis arrested using cardiopulmonary bypass procedures, the presentinvention has even greater value in a beating heart wherein anastomoticsite 16 must be stabilized for the grafting process.

FIGS. 2-9 are perspective and side elevational views of variousalternative embodiments of the present invention system. FIG. 2 providesa perspective view of the present invention system comprising pad 11,control arm 12 connected to pad 11 wherein control arm 12 terminates inattachment member 13. Attachment member 13 in this embodiment is a ringthat facilitates easy grasping by a surgical instrument such as agrasper, a retractor or the like. Control arm 12 is attached to pad 11by use of adhesive 14, preferably the same adhesive used to bond pad 11to myocardium 6. Pad 11 appears in FIGS. 1 and 2 as small rectangles,but other shapes and sizes are contemplated depending upon surgicalconstraints. In addition, pad 11 is preferably made from a pliablematerial so that it easily conforms to match the surface contours ofmyocardium 6.

Control arm 12 is made from a rigid or semirigid material and furtherincludes optional feet 15 that spread outward to obtain torsional andbending control of pad 11. This control arm, pad, and retractor systemallows six degrees of control of the structural pieces in the X, Y, andZ axes along with moments about each of those axes.

Feet 15 can have any number of outstretched toes dispersed in a varietyof angles and configurations. Control arm 12 preferably has acylindrical shape, or it can have a polygonal shape cross-section.

In one exemplary embodiment, pad 11, control arm 12, and adhesive 14 aremade from bioabsorbable materials. After the surgical operation, controlarm 12 can be cut and removed while feet 15, pad 11, and adhesive 14 areleft behind to dissolve within the patient. In an exemplary embodiment,adhesive 14 is made from is a bioabsorbable copolymer such as, forexample, poly-L-lactic acid (L-PLA), polycaprolactone (PCL), collagenbased adhesive, albumin based adhesive, and fibrin based adhesive. Pad11 and control arm 12 are preferably made from bioabsorbable materialssuch as, for example, polyglycolic acid (PGA), poly-L-lactic acid(L-PLA), polyorthoesters, polyanhydrides, polyiminocarbonates, inorganiccalcium phosphate, polyorthoesters, aliphatic polycarbonates, andpolyphosphazenes.

FIG. 3 provides a side elevational view of an alternative embodiment ofthe present invention system attached to myocardium 6 adjacent vessel orartery 16. In this embodiment, the system includes mechanical interlock17 bonded by optional pad 18 to myocardium 6 by use of adhesive 19.Traction frame 20 having interior opening 21 that mechanically lockswith the complementary shape of interlock 17 thereby interconnecting thetwo structures. Specifically, interlock 17 can have a ball orcylindrical shape while opening 21 can have a complementary tubularcavity to link up therewith. Sliding the traction frame 20 laterallywould connect and disconnect opening 21 to and from interlock 17.

Traction frame 20 includes control arm 23 that terminates in anenlarged, grippable structure such as textured end 24 as shown. Texturedend 24 is grasped by a retractor to manipulate the tissue connected topad 18. Thus, through the present invention system, it is possible tolift and pull myocardium 6 thereby locally stabilizing anastomotic site22. If interlock 17, pad 18, and adhesive 19 are made from bioabsorbablematerials, they can be left behind after the procedure to dissolvewithin the patient after traction frame 20 is disconnected therefrom.

FIG. 4 provides a side elevational view of an alternative embodimentwhere pad 25 has at least one barb 26 embedded into myocardium 6. Thebarb(s) 26 assist in attaching pad 25 to myocardium 6. Each pad 25includes suture 27 bonded to pad 25 by use of adhesive 28. Of course,sutures 27 can be replaced with rigid or semirigid control arms in analternative embodiment. The sutures 27, are in turn, connected to anoptional frame (not shown) that is positioned outside the patientencircling the limited thoracotomy or sternotomy used for cardiacaccess. Alternatively, sutures may be attached to a frame that is inturn attached to the operating table.

FIG. 5 provides a side elevational view of an alternative embodimentsystem providing preferably helix-shaped fasteners 29 for embedding intomyocardium 6 on either side of artery 10. FIGS. 6(a) and 6(b) provide aside elevational view and a top plan view, respectively, of a preferredembodiment of the helix-shaped fastener 29. As seen in FIG. 5, thehelix-shaped fastener 29 is ideally inserted into myocardium 6 adjacentanastomotic site 22 of coronary artery 10 by means of a mechanicalinsertion device or manually.

A second helix-shaped fastener 29′ and associated suture 30′ areinserted on the opposite side of artery 10 and tension is applied tosuspend and stabilize anastomotic site 22 by use of sutures 30, 30′attached to fasteners 29, 29′. In the preferred embodiment, helix-shapedfasteners 29, 29′ are manufactured from a rigid, bioabsorbable material.Rigidity of fasteners 29, 29′ is required to allow insertion intomyocardium 6; use of a bioabsorbable material allows fasteners 29, 29′to be left in heart 5 following coronary bypass surgery without need forremoval. Sutures 30, 30′ attached to the fasteners 29, 29′ may also bebioabsorbable, such that following use, sutures 30, 30′ may be cut closeto the respective fasteners 29, 29′ and the remaining short end leftbehind. Although only two fasteners 29, 29′ are shown, more or fewerfasteners can be used depending on the surgical requirements.

The outer diameter of helix-shaped fasteners 29, 29′ may need to besomewhat larger than four millimeters and it is anticipated that theideal diameter ranges between five millimeters and eight millimeters, asdetermined through empirical observations.

Moreover, sutures 30, 30′ may be attached to a frame outside the surfaceof the skin, wherein the frame may encircle the limited thoracotomy orsternotomy used for cardiac access. Sutures 30, 30′ may be attached to aframe which is also itself attached to the operating table. Preferably,helix-shaped fastener 29, 29′ includes a beveled tip 31 so that it caneasily drive into myocardium 6. Of course, the number of coils,dimensions, length, and pitch of helix-shaped fasteners 29, 29′ can bevaried in accordance with design requirements.

The mechanical insertion device used to deliver helix-shape fasteners29, 29′ can be of the type known commercially as the ORIGIN TACKER™,manufactured by Origin Medsystems, Inc., Menlo Park, Calif. Inparticular, this spiral tacking device is essentially a hand operated,pistol grip feeder of the helix-shaped fasteners wherein thehelix-shaped fasteners are ejected from the front end of a feeding tubein which the fasteners are contained. Use of such a device for fixationof mesh in laparoscopic hernia repair is described in an articleentitled “A Novel Technique for Anterior Hernia Repair” by Harold S.Golstein, M.D. and was published by Origin Medsystems in 1996.

FIG. 7 is a side elevational view of an alternative embodiment of thepresent invention system comprising control arm 31 with outstretchedfeet 32 and attachment member 33 disposed on opposite ends. In thisembodiment, feet 32 are embedded in a mound of adhesive 34. Thus, feet32 are directly bonded to myocardium 6 without use of a pad as seen inthe embodiment of FIG. 2. Again, adhesive 34, feet 32, and control arm31 are made of bioabsorbable material so that at the conclusion of theoperation, control arm 31 can be clipped off with only the lower stemand feet 32 left behind along with adhesive 34, all of which eventuallydissolve.

A retractor can grasp the ring-like attachment member 33 to manipulateand control anastomotic site 22 via feet 32 and adhesive 34. Again, moreor fewer of the present invention devices can be used at a specificanastomotic site.

FIG. 8 is a side elevational view of an alternative embodiment of thepresent invention system having pad 35 with a suture 36 attached to thetop surface of pad 35, while the bottom surface includes at least oneminiature suction cup 37 which adheres in a conventional manner tomyocardium 6. Alternatively, an adhesive can be added to strengthen thebond between suction cups 37 and myocardium 6. Suture 36 of course canbe replaced with rigid or semirigid control arms as in some of the otherembodiments. Any of the foregoing can be made from bioabsorbablematerials.

FIG. 9 is a side elevational view and FIG. 10 is a partial perspectiveview of an alternative embodiment of the present invention systemproviding short lengths of tubing 38 that are directly bonded tomyocardium 6 using adhesive 39. Outer lip 40 of tubing 38 provides easyaccess and grasping by a surgical instrument such as a retractor tostabilize anastomotic site 22. Outer lip 40 also serves as an attachmentmember or platform so that other components can be attached or bondedthereto.

In yet another alternative embodiment, another more rigid section oftubing can be inserted inside hollow opening 41 of tubing 38 to serve asthe control arm and for easier access by the retractor. Tubing 38 alongwith adhesive 39, if made from a bioabsorbable material, can be leftbehind after the surgical procedure.

Other modifications can be made to the present invention withoutdeparting from the scope thereof. The specific dimensions, shapes, andmaterials of construction are provided as examples, and substitutes arereadily contemplated which do not depart from the invention.

What is claimed is:
 1. A system for stabilizing a local area of abeating heart during a surgical procedure, the system comprising: amechanical device attached to the local area of cardiac tissue bypenetrating the cardiac tissue in the local area; and a structureincluding a suture attached in tension to the mechanical device forcontrolling the mechanical device and thereby manipulating the localarea of cardiac tissue to stabilize the local area.
 2. A system forstabilizing an anastomotic site of a vessel of a beating heart during asurgical procedure, the system comprising: a first helix inserted intocardiac tissue at the anastomotic site at a first position; and a sutureattached to the first helix and tensioned to suspend and stabilize theanastomotic site.
 3. The system of claim 2, wherein the first helixincludes a distal end having a beveled tip.
 4. The system of claim 2,wherein the first helix is rigid.
 5. The system of claim 2, wherein anoutside diameter of the first helix is about 4 mm.
 6. A system forlocally stabilizing an anastomotic site about a vessel of a beatingheart during a surgical procedure, the system comprising: a first helixfor insertion into the anastomotic site at a first position; and asuture attached to the first helix for connection to an external framefor tensioning the suture to suspend and stabilize the anastomotic site.7. A method for stabilizing an anastomotic site of a vessel during asurgical procedure, comprising the steps of: providing a firsthelix-shaped fastener; embedding the first helix fastener into tissuesurrounding the anastomotic site; attaching a first suture to the firsthelix fastener; and tensioning the first suture to suspend and stabilizethe anastomotic site.
 8. The method of claim 7, wherein the methodfurther comprises the steps of providing a second helix-shaped fastener,embedding the second helix fastener into tissue surrounding theanastomotic site, and attaching a second suture to the second helixfastener.
 9. The method of claim 8, wherein the step of attaching thesecond suture further comprises the step of tensioning the second sutureto suspend and stabilize the anastomotic site.
 10. The method of claim8, wherein the method further comprises the steps of providing a thirdhelix-shaped fastener, embedding the third helix fastener into tissuesurrounding the anastomotic site, and attaching a third suture to thethird helix fastener.
 11. The method of claim 8, wherein the first andsecond helix fasteners are disposed around the anastomotic site so thatthe vessel is positioned between the fasteners.
 12. The method of claim7, wherein the method further comprises the step of cutting the firstsuture.
 13. The method of claim 7, wherein the step of embedding thefirst helix fastener further comprises advancing the first helixfastener axially into the tissue.
 14. The method of claim 7, wherein theembedding step includes embedding the first helix fastener into themyocardium of the heart at a position adjacent to a coronary artery. 15.A system for locally stabilizing the myocardium adjacent to ananastomotic site of a coronary artery of a beating heart during asurgical procedure, the system comprising: a first helix-shaped fastenerfor insertion into the myocardium adjacent the coronary artery; a secondhelix-shaped fastener for insertion into the myocardium adjacent thecoronary artery; and at least one suture attached in tension to each ofthe first and second helix fasteners to stabilize the myocardium and thecoronary artery.
 16. The system of claim 15, wherein the first andsecond helix-shaped fasteners are formed from a bioabsorbable material.17. A system for locally stabilizing a beating heart during a surgicalprocedure, the system comprising: a mechanical device of biodegradablematerial attached to a local area of cardiac tissue by penetrating thecardiac tissue in the local area; and a structure for controlling themechanical device and thereby manipulating the local area of cardiactissue to stabilize the local area.
 18. A system for locally stabilizingan anastomotic site of a vessel of a beating heart during a surgicalprocedure, the system comprising: a first helix inserted into theanastomotic site at a first position; a suture attached to the firsthelix and tensioned to suspend and stabilize the anastomotic site; asecond helix inserted into the anastomotic site at a second position;and a suture attached to the second helix and tensioned to suspend andstabilize the anastomotic site.
 19. The system of claim 18 comprising athird helix for insertion into the anastomotic site at a third position.20. A system for locally stabilizing an anastomotic site of a vessel ofa beating heart during a surgical procedure, the system comprising: afirst helix formed from a bioabsorbable material inserted into theanastomotic site at a first position; and a suture attached to the firsthelix and tensioned to suspend and stabilize the anastomotic site. 21.The system of claim 20, wherein the suture is bioabsorbable material isselected from the group of materials consisting of polyglycolic acid(PGA), poly-L-lactic acid (L-PLA), polyorthoesters, polyanhydrides,polyiminocarbonates, inorganic calcium phosphate, polyorthoesters,aliphatic polycarbonates, and polyphosphazenes.
 22. A system for locallystabilizing an anastomotic site of a vessel of a beating heart during asurgical procedure, the system comprising: a first helix inserted intothe anastomotic site at a first position; and a suture formed from abioabsorbable material attached to the first helix and tensioned tosuspend and stabilize the anastomotic site.
 23. A system for locallystabilizing an anastomotic site of a vessel of a beating heart during asurgical procedure, the system comprising: a first helix formed fromtitanium inserted into the anastomotic site at a first position; and asuture attached to the first helix and tensioned to suspend andstabilize the anastomotic site.
 24. A system for stabilizing a localarea of a beating heart during a surgical procedure, the systemcomprising: a mechanical device attached to the local area of cardiactissue by penetrating the cardiac tissue in the local area; and astructure including a mechanical fastener for slidable attachment to anexternal frame for controlling the mechanical device and therebymanipulating the local area of cardiac tissue to stabilize the localarea.